The present invention relates to a bolt repositioning device for firearms, particularly for semiautomatic rifles.
In this type of firearm, a compromise is normally made between the rigidity of the recoil spring and the setting of the system, so that the weapon can fire cartridges with a variable charge. Powerful cartridges in fact require a stronger recoil spring, which however does not allow a reliable operation of the bolt assembly when using weak cartridges. Vice versa, a less rigid spring, suitable for weaker cartridges, is insufficient when using powerful cartridges and causes operating problems such as, for example, a slowing down of the bolt closing action. The strong recoil impact also causes inaccuracy and discomfort for the gunner.
Adjustment systems are known, such as for example the barrel brake ring in long-recoil rifles, or the maximum-pressure valve in gas-intake rifles, by means of which it is possible to make the weapon suitable for the use of cartridges with different charges; however, this adjustment is effective for a narrow range of cartridges.
Furthermore, the progress made in the manufacture of cartridges, the introduction of steel shot, and the use of special cartridges in the sports field have further increased the gap between weak cartridges and powerful cartridges.